Reversible internal combustion engine



Jan. 13, 1942. A. NAsHoLM REVERSIBLE INTERNAL COMBUSTION ENGINE Filed Sept. 16, 1939 4 Sheets-Sheet 1 O 7 Z 1 in a R 0o 8 7 6 W v w 0 W 6 W N 5 I 7 ,R 5 0 l 6 7 V wm 0 0 no 1,.. I N 2 M A m I fl l 1 Q i 0 8 w J 0. l I I 1| 4 6 n. m w 4 a m 5 5 I, W 1 Z W W 4 1/ z 011d 6 9- a d W 5 5 M w 1 A 4 Fig! Jan. 13, 1942. A. NAsHoLM I 2,269,547

REVERSIBLE INTERNAL COMBUSTION ENGINE Filed-Sept. 16, 1939 4 Sheets-Sheet 2 6 nvv NTOR.

Jan. 13, 1942. v A, NASHQLM 2,269,547

REVERSIBLE INTERNAL COMBUSTION ENGINE Filed Sept. 16, 1959 4 Sheets-Sheet 4 Patented Jan. 13, 1942 REVERSIBLE INTERNAL COMBUSTION ENGINE ,J

Alfred Nasholm, Goteborg, Sweden, assignor to Aktiebolaget Gotaverken, Gotebor Sweden, a corporation of Sweden Application September 16,1939; ser al-N0. 295,211

In Sweden September T1,;- 1938 Claims. (c1. lea -14,1)"

This invention relates to improvements in reversible internal combustion engines having a control member movable in two opposite directions and adapted for reversing the direction of rotation of the internal combustion engine and/or for controlling the fuel supply of the internal combustion engine in both directions of rotation.

One object of the invention is to effect a reliable setting, for instance of cam shafts for fuel pumps and/or valves in positions for operation of the engine ahead or reverse.

A further object of the invention is to prevent incorrect operation of the engine, for instance through fuel supplyto the engine at other moments or in other ways than intended for operation ahead or reverse, respectively.

According to the invention I provide a blockin member which may be set in two different positions and which is provided with two stops, one of which is always in the path of the movable control member in either of said positions, said blocking member being arranged, depending upon the momentary direction of rotation of the engine, to take the position, in which the control member is prevented from being set for operation of the engine in the opposite direction of rotation.

Further features of the invention are set forth in the following specification and claims.

In the accompanying drawings one embodiment of the invention is illustrated by way of example.

Fig. 1 is a diagrammatic perspective view of a two stroke solid injection internal combustion engine provided with a. control mechanism in which the invention forms a part.

Fig. 2 is a front view of a control wheel.

Fig. 3 illustrates the starting gear in detail on a larger scale.

Figs. 4 and 5 are details of the starting gear in different positions.

Fig. 6 illustrates the reversing gear, and

Figs. '7 and 8 are sections on lines VII-VII and VIII-VIII in Fig. 6.

Figs. 9 and 10 illustrate a portion of the fuel supply control gear in operative and unoperative position, respectively, and

Fig. 11 is a diagrammatic view of the fuel supply control gear in different positions.

In. Fig. 1, I?! designates a portion of a bed of a single acting twostroke solid injection internal combustion engine and I69 a partly broken away crank case of one cylinder of said engine. A main crank shaft I'IU of the engine is mounted in bearings H2 and I13 carried by supports pro- -videdonthe bed I I I. In the drawings, one cylinder 'IM' onlyis illustrated, but the engine may naturally comprise two or several cylinders. I15

'indicatesamanifold for charging and scavenging' air and I16 is an exhaust manifold connected with the engine. The crank shaft H0 is provided -.with crank arms III carrying cams I18,

which actuate bell crank levers I'I9 connected by means of rods I89 with a cross beam I8I mounted on top of the cylinder andcarrying an exhaust valve I82.

The control mechanism of the illustrated internal combustion engine comprises a control shaft I, which may be turned to the left and to the right by means of a control wheel 2 and which is mounted in bearings I83 supported by the bed Ill. The control shaft I carries actuating means for the starting, reversing and fuel control gears, In Fig. 1 all parts are illustrated in the position which they take when the engine is at rest after havin been operated ahead.

A main starting air valve 3 is connected through a conduit 4 with a not illustrated container or other source of compressed air. .The main air valve 3 is operated by means of a wheel 5, the operation of which causes starting air to be firstly supplied to a conduit 6 leading to'a pilot valve I and upon further rotation of the wheel 5 to a conduit 8. The pilot valve I is connected with a valve housing I9 of a slide valve I I, Fig. 3, by means of a conduit 9. A disk I2 is wedged onto the control shaft I and carries two cams I3 and M' disposed symmetrically and mounted pivotally on said disk. Said cams are normally kept in the position illustrated in Figs. 1 and 3 by springs I5 and I6. A piston valve" is displaceable in the pilot valve housing I and has grooves I8 and I9, respectively, in the upper and lower ends, said piston valve being actuated by a tappet 2t guided in the lower portion of the pilot valve housing I. In the lower position of the valve I! the groove I8 forms a connection between the conduit 6 and. the conduit 9, as obvious from Fig; 3. The pilot valve housing I is provided with air outlet openings 2I in the lower portion- When the valve I1 is in the lower position, the connection between the interior of the pilot valve housing I and said air outlet openings 2I is interrupted and the piston valve I7 is pressed downwards by the air pressure above the valve. When the wheel 2 is turned to the left from the position illustrated in Figs. 1 and 2 the tappet 29 rides over the cam I3, as illustrated in Fig. 4, during the first por- I84, 22 to th starting air valves 23. pilot valve 'I-due to the turning of the wheel 2 to th -left or to the right is actuated by one of thecams I3 or I4 and connects the conduit 9 with the atmosphere the air pressure in the concommunication with the chamber 34. 36 isconnectedat the top of the starting air "valve-23 and connects the starting air valve 23 tion of the turning of the control wheel, that is during the portion of the turning, which in Fig. 2 is indicated by "Start ahead. The piston valve I1 is then forced upwards by the tappet 20 and the connection between the conduits 6 and 9 is interrupted, and the conduit 9 is instead connected with the atmosphere through the groove I9 and the air outlet openings 2|, Fig. 4. Upon continued turning of the control wheel 2 to the left the corner of the cam I3 passes the valve tappet 20 and the compressedair above the piston valve II forces the piston valve and the valve tappet 2D downwards causing the piston valve to shut off the connection between .the conduit 9 and the atmosphere and to re-establish the connection between the conduit 6 and the conduit 9 through the grooves I3. Upon-continued turning of the control wheel 2 to the left the pilot valve I is not further affected. When the control wheel is returned to the stop position the cam |3-is only moved away from the valve tappet 20 due to the weakness of the spring I without actuating said valve tappet, as illustrated in Fig. 5.

When' the control wheel 2 is turned to the right from 'the-stop position, the pilot valve I is actuate'd in amanner corresponding to the above described operation by the cam I4 of the disk I2. The upper portion of the housing Ill of the slide valve I I is connected with the conduit 9 and atone side of the housing the conduit 8 is connected. A conduit I84 is connected with the lowerportion of the slide valve housing I0 and connects said portion'with conduits 22 leading tostarting air valves 23 disposed on the motor cylinders H4. The slide valve housing I0 comprises-an upper chamber 24 and a small lower chamber 25 and the slide valve II forms a comparatively large piston 26 movable in the upper chamber- 24 above the inlet of the conduit 8. A spring This provided between the piston 26 and the top of 'the slide valve housing I0, which spring and the airpressure in the conduit 9 normally keep the slide valve II depressed in the lower'position, in which it is illustrated in Fig. 3. The slide valve II is provided with a guide 28 at the lower portion and at an intermediate portion with a valve member 29, which in the lower position of the slide valve interrupts the connec- 'tiOn between the chambers 24 and 25 of the slide valve housing It) and thereby prevents the compressed air in the conduit 8 from passing the slide valve and from'fiowing through the conduits When the duit"'8 is capable of moving the slide valve up- Then the compressed The starting air valve 23 comprises a spindle 39 provided with-a large upper piston 3| dis- 'placeablein a chamber 32, a piston 33 displace- "ab'le in a chamber 34-and at the lower end with a valve member 35 serving to close or open the "connection between the chamber 34 and the motor cylinder I14. The conduit 22 is in constant A conduit with a starting air distributor 37. In Figs. 1 and 3 a second starting air distributor 38 is also illustrated, which in th same manner as the starting air distributor 31 is connected to a not illustrated starting air valve of another motor cylinder through a conduit 39. A starting air distributor shaft 46 driven from the motor shaft and mounted in bearings I85 carries a sleeve 4|, which is longitudinally displaceable but not rotatable on said shaft. Said sleeve is provided with a cam 42for each starting air distributor adapted to control the starting air distributor when the engine is started ahead and with a cam 43 controlling the starting air distributor, when the engine is startedfor movement in reverse direction. A bell crank lever 45, 46 is mounted on a pivot 44, and one arm of said lever engages a groove 47 in the sleeve 4| and is adapted to cause displacement of the sleeve to a position in which the ahead cams 42 or the astern cams 43 are disposed beneath the valve stems 48 of the starting air distributor valves 49. In order to enable the sleeve -4I always to be moved to the desired position in spite of the momentary position of the cams'42, 43 the high portions of the cams are chamfered, as indicated in Fig. 3. An upper chamber'5ll, which is closed by a cover 5| in the starting air distributors, is in continuous com- "munication with the conduit I84 from th lide 'valve I 3 through a conduit 52, and as soon as compressed air is admitted to said conduit the valves 49 are pressed downwards by the compressed air, which flowsinto the chambers 50. The stems 48 of the valves 49 are provided with 'recesses 53, which in the lowermost position of the valve form a connection between chambers 54 and 55 of the starting air distributors. The

"chambers55 are continuously connected with the atmosphere through ducts 56. Consequently,

when the valves 49 are in bottom position, the

top of thepiston 3| of the starting air valve 23 is connected with the atmosphere through the conduit 36, the chamber 54, the recess 53, the chamber-55 and the duct 55. The starting air valve is then pressed upwards by the compressed airand thus kept closed. When the valve stem 48is lifted by one of the cams 42 or 43 the con- "gives the compressed air free admission to the motor cylinder.

The displacement of the sleeve 4| on the starting air distributor shaft 40 is produced by turning of the control wheel 2 to the left or to the :right by means of a double cam disk 51 secured on the control shaft I, as illustrated in Figs. 1 and 3. The cam disk 5'! is provided with a cam 58 co-operating with a roller 59 mounted on a bell crank member 59. The arm 6| of the bell crank member 30 is connected with the arm 45 of the bell crank lever 45, 46 by means of a rod The cam disk 51 is provided with a second cam 63 and the bell crank member has a roller 64 mounted thereon and co-operating with the last mentioned cam. The bell crank member is mounted on a shaft 65 carried by a suitable sup- -port 66in ahousing 89 provided on the bed I'II. --When the control wheel 2 is turned to the left, "the roller 59 travels up the cam 58 and the roller .34 moves towards the lower portion of the cam T63 while thebell crank member 69 is turned to beneath the valve stems '48.

the right. The arm 6I and the arm 45 are then moved upwards and the sleeve M is displaced to the left in Fig. 3 so that the ahead cams 42 are disposed just beneath the valve stems 48. If the control wheel 2 is instead moved to the right, the roller 64 travels up the cam 63 and the roller 59 moves towards the lower portion of the cam 58 so that the arms 6| and 45 are moved downwards and the sleeve M is moved to the right in Fig. 3 causing the astern cams 43 to be set just vention is not limited to the employment of the above described starting air valve control gear and the described reversing gear for the starting air distributors, and instead of pneumatic control of the starting air valves mechanical control of said valves may be used comprising for instance a cam shaft, which may be set in two different ways for opening and closing of the starting air valves for starting ahead or reverse by means of actuating means provided on the control member I.

A fuel injection valve 6'! of conventional design is connected through a conduit 68 with a fuel pump 69, for instance of the Bosch type. Fuel is supplied to said pump through a conduit I8. As usual, the pump comprises a plunger II provided with a sloping recess I2 and adapted to be turned around its longitudinal axis by means of a lever I3, a rod I4 and a lever 15 on a shaft I6 mounted in bearings I81 in the crank case I89. The effective stroke of the plunger H is varied by turning the plunger, and consequently the fuel quantity injected at each stroke is varied in such a manner that a turning movementof the lever I3 to the right in Fig. 1, after the sloping edge of the recess I2 has reached a position just opposite the opening of the fuel supply conduit 18, results in an increased fuel injection per stroke of the fuel pump, since the effective length of the pump stroke is thereby increased from zero to maximum. The shaft 16 carries one or several additional levers H, which actuate not illustrated fuel injection pumps for the other cylinders of the motor by means of rods I8. is provided with a lever I9, which is connected with one end of a rod 83 by means of a rod 88 and a double armed lever 8! mounted on a pivot 82, Figs. 9 and 10. In Fig. 1 the lever I9 is shown connected directly with the end of the rod 83 for the sake of simplicity, it being understood that this modification does not materially change the operation of the disclosed mechanism. The rod 83 is connected with the free end of a connecting rod 84 pivotally mounted on a crank 85 formed by the control shaft I. The free end of the connecting rod 84 is guided along a sloping guide 86 formed by a slot in a member 81, which is mounted on a pivot 88 in the housing 89, Figs. 9 and 10. The pin 98 of the connecting rod 84 is provided with a roller 9|, which is guided in the slot 86. In Figs. 1 and 9 the control shaft I is illustrated in a position in which no fuel supply takes place. Due to the design of the recess I2 in the pump plunger II, illustrated in Fig. 1, fuel supply is prevented until the control wheel has been turned to the right or to the left over the whole starting period, Fig. 2. Obviously, .the turning of the control wheel 2 in either direction past the starting period causes the free end of the connecting rod 84 to move further and further up the slot 86 so that the rod 83 is moved upwards and the fuel injection per stroke of the fuel pump increased. In order to maintain the member 81 in a fixed position on the pivot 88,

Naturally, the in-' The shaft 16 a catch 92 is-provided in the housing 89 and forced by a spring 93 into a notch 94 in the member 81. 95 is a rod connected by a link 96 with an extension 91 of the member 81. The rod 95 may, for instance, be connected with an over speed governor I 88, Fig. 1, which may, for instance, be of the well known Aspinall type having a swinging arm I89 moved up and down by the engine and provided with two detent means, movable by mass forces, said means being adapted toengage a normally passive arm I88, one detent means forcing the arm I88 downwards for cutting out or reducing the fuel supply of the engine, when a predetermined speed is exceeded, and the other detent means being adapted to force the arm I88 upwards for restoration of the fuel supply of the engine as soon as the speed of the engine has decreased below a predetermined value. Thus, if the internal combustion engine speeds the arm I89 forces the arm I88 and the rod 95 downwards. The member 81 is then tilted on the pivot 88 and an extension 98 of the member 81, which forms one side of the guide way 86, then forces the free end of the connecting rod 84 downwards and simultaneously pulls the rod 83 downwards so that the levers I5, II-are turned to the left in Fig. 1 and fuel supply is substantially shut off.

The plungers 'II of the fuel pumps are provided with push rods 99 bearing with rollers I88 on cams I8I, I82 on a shaft I83, which is mounted in suitable bearings I98 in the crank case I69 and drives the fuel pumps. As illustrated in Fig. 7, the cams I8I are of symmetric design and consequently the cams actuate the fuel pumps in the same manner upon rotation in either direction. A sprocket I84 is mounted on the shaft I83 so that it can rotate on the shaft but is fixed longitudinally thereon. The sprocket I84 is driven by a chain I9I from a sprocket I92 on the crank shaft I18. The sprocket I84 is connected with further sprockets I93 and I94, which through chains I95 and I96, respectively, drive the Aspinall governor I89 and the starting air distributor shaft 48, respectively. The right end of the hub of the sprocket I84 forms a clutch member I85, which is provided with two sector shaped jaws I86 and IN, as illustrated in Fig. 7. The clutch member I85 co-operates with another clutch member I88, which is secured on the shaft I83 and provided with sector shaped recesses I89 and H8, which are partly occupied by the jaws I86 and IN, respectively. The portions of the recesses I89 and H8 not occupied by the jaws I86 and I8? subtend an angle a and are confined by jaws III and H2 formed in the clutch member I88. Obviously, the shaft I83 may be turned the angle or relatively to the sprocket I84, while the cam I8I moves from the position illustrated in dotted lines to the position illustrated in chain' dotted lines in Fig. '7. The sprocket I84 is driven from the motor shaft as above indicated, and for looking it relatively to the clutch member I88 in either of the indicated positions the left end of the hub forms a clutch member H3 adapted to co-operate with a clutch member H4, Fig. 6, which is longitudinally displaceable but nonrotatable on the shaft I83. The clutch member H4 is provided with jaws H5, H6 adapted to cooperate with jaws II'I, H8 in the clutch member I I3 formed by the sprocket I 84, see Fig. 8. A ring I I 9 is secured on the shaft I83. Said ring carries Ithree springs I28 secured on studs I2I and extending into bores I22 in the clutch member I I4 .andserving to bring said member into engagement with the clutch member II3.

A screw threaded collar I23 is secured on the clutch member H3 and co-operates with another screw threaded collar I24, which is displaceably but somewhat modified form, in which the rod I30 and the lever I3I for the sake of greater simplicity have been omitted. The link I33 15 connected with a swingable angle member I35, which is mounted on a pivot I34 and movable into two different positions depending upon the position of the collar I24 on the collar I23. The pivots I32, I34 are carried by a suitable housing I36, Fig. 6, which also forms bearings for the control shaft I. The clutch member H4 is provided with a groove and a ring I31 engages said groove and is connected with a fork shaped arm I38 of a bell crank lever I38, I39 mounted on a pivot I40. The arm I39 of the bell crank lever is adapted to be actuated by a spindle I4I slidable in a housing I42 under the action of a piston I43. The upper portion of the housing I42 is provided with a conduit I44, which connects the housing with a chamber I45 in a pilot valve I46 disposed at the housing I36 and provided with a second chamber I41, which is connected to the compressed air conduit 8 between the main air valve 3 and the slide valve housing I by means of a conduit I48. The pilot valve housing I46 contains a second chamber I49 connected through openings I56 with the atmosphere. A piston valve lI is slidable in the pilot valve housmg I46 against the action of a spring I52 in the chamber I41. The piston valve I5I is provided with grooves I53, which in the lower position of the piston valve connect the housing I42 and the conduit I44 with the chamber I49 and the atmosphere. In the upper position of the piston valve the connection between the conduit I44 and the atmosphere is interrupted, and then the grooves I53 form a connection between the conduit I48 and the conduit I44 through which compressed air may flow to the housing I42 and depress the piston I43 and the spindle MI and thus through the bell crank lever I38, I39 bring the clutch member I I4 to disengage the clutch member II3 on the sprocket I04.

The angle member I35 carries two stops or tappets I54 and I55. which are slidably mounted in the angle member, as obvious from Fig. 6. The lower ends of the tappets I54, I55 continuously rest on a sliding member I56 mounted in the. housing I36, whereas the upper ends of the tappets form stops. The sliding member I56 is provided with an opening I51, in which one arm I56 of a double armed lever I58, I60 mounted on a pivot I59 is inserted. The lever arm I60 carries a set screw I6I, which bears against a valve tappet I62 co-operating with the piston valve I5I and longitudinally displaceable in a guide I63, against which the valve tappet I62 is pressed by a spring I64. A double faced cam I65 is secured on the control shaft I and adapted to cooperate with the tappet I54 or I55, when the control shaft is turned.

The control mechanismabovedescribed and illustrated in the drawings operates in the following manner:

In the drawings the control mechanism is illustrated in the position, which it takes, when the engine is at restready for starting ahead.

Before starting the main air valve 3 is completely opened. During this opening movement the conduit 6 is at first brought under pressure and compressed air flows through the conduit 6, the pilot valve 1, which is in the position illustrated in Fig. 3, and the conduit 9 to the top of the slide valve II, which is consequently at first subjected to the downward action of the starting air pressure and the spring 21 so that the slide valve with the valve piston 29 is sure to keep the connection between the chamber 24 and the chamber 25 in the slide valve housing I0 interrupted before compressed air is admitted to the chamber 24. During the continued opening movement of the main air valve the openingto the conduit 8 is successively uncovered and compressed air is admitted through said opening into the chamber 24 of the slide valve housing I0. Then the same air pressure prevails on top and beneath the upper piston 26 of the slide valve and the slide valve is still kept closed in the lower position through the action of the spring 21. When compressed air is admitted to the conduit 8 the compressed air flows through the conduit I48 to the chamber I41 in the pilot valve I46 (see Fig. 6). Assuming that the angle member I35 is in the position illustrated in Fig. 6 the control mechanism is now ready for starting the engine ahead or reverse.

If the engine is to be operated ahead, the following operations are carried out:

The control wheel 2 is turned to the left, Figs. 1 and 2. During the first portion of said turning movement the roller 59 on the bell crank member 60, Fig. 3, travels up the cam 58 on the control shaft I and the roller 64 simultaneously moves towards the lower portion of the cam 63. The arm BI is consequently moved upwards as is also the rod 62 and the arm of the bell crank lever 45, 46. The cams of the sleeve M on the starting air distributor shaft 40 are then moved to the left in Fig. 3 or to the right in Fig. 1, respectively, so that the ahead cams 42 are disposed below the valve stems 48. Upon further turning of the control wheel 2 to the left the cam I3 on the disk I2 actuates the valve tappet 20 of the pilot valve 1. At the end of the starting period, Fig. 2, the cam I3 has forced the valve tappet 20 and the piston valve I1 to the position illustrated in Fig. 4. By this movement the conduit 9 and the chamber on top of the piston 26 in the slide valve housing I0, which was previously under the influence of the starting air pressure through the grooves I9 and the openings 2I of the pilot valve 1, has been connected with the atmosphere. Simultaneously, the piston valve I1 has shut off the conduit 6. When the pressure is relieved on top of the slide valve piston 26 the compressed air in the chamber 24 forces the slide valve I I upwards against the action of the spring 21, Fig. 3. The piston 29 then opens a passage for the compressed air from the chamber 24 to the chamber 25 in the slide valve housing I 0, and compressed air flows through the conduit 22 to the chamber 34 in the starting air valve 23. If a sufiicient number of cylinders of the internal combustion engine are provided with starting air valves and corresponding starting air distributors, there will always be a starting air distributor in such a position that the pertaining valve 49 has been forced upwards at the above mentioned movement of the sleeve 4I The connection between the conduit 36 and the atmosphere through the chamber 54, the recesses 53, the chamber 55 and the ducts 56 is always interrupted in said starting air distributor, and the pertaining conduit 36 instead communicates with the conduit 52, through which compressed air is supplied to the starting air distributor. Consequently, compressed air flows through the conduit 36 into the space above the piston 3I in the starting air valve 23 and forces said piston downwards so that the valve member 35 is opened. The compressed air then flows from the conduit 22 through the chamber 34 into the motor cylinder and moves the working piston of said cylinder. The motor is now driven on the starting air, and the starting air distributors 31, 38 etc., in turn open and close the compressed air supply to the motor cylinders, which are provided with starting air valves. Closing of the starting air valves 23 is then produced by the starting air distributors, which at proper moments bring the top of the respective starting air valve piston 3I in connection with the atmosphere.

If an insufficient number of motor cylinders are provided with starting air valves, it may occur that the starting air distributor shaft 40, when the compressed air is admitted to the conduit 52, is in such a position that no valve 48, 49 is lifted, and to start the motor in such a case it is obviously necessary to turn the motor shaft by means of suitable devices to a position, in which one of the valve stems 48 is lifted by the corresponding cam.

When the control wheel 2 is in the stop position the parts 85, 84, 90, 83 and BI take the position I indicated in full lines in Fig. 11. The member 81 is then kept in the position illustrated in Fig. 9 by the catch 92, which engages the notch 94. During the turning of the control wheel 2 from the stop position I 66 to the position I61, the angle n in Fig. 11, the motor has been started, and if the control wheel is not turned further, the motor runs ahead on the starting air. During this turning movement the crank 85 has been turned so far that the plunger H of the fuel pump is just about to reach operative position. Upon further rotation of the control wheel 2 past the position I61, i. e. within the angle 1 in Fig. 11, the plungers H of the fuel pumps are additionally turned, since the free end of the connecting rod 84 with the roller 9| moves higher up in the guide way 86 so that the rod 80 is pulled downwards and by means of the levers 19 and 15, the rod 14 and the lever 13 turn the pump plunger 1I still more so that the fuel injection starts. At this continued turning of the control wheel 2 the pin 90 moves along the curve I91, Fig. 11. When the wheel 2 has been turned past the position I61 the cam I3 passes the valve tappet 28 and the pressure in the conduit 6 then forces the piston valve I1 in the pilot valve housing 1 downwards so that the connection between the conduit 9 and the atmosphere is interrupted. A connection is instead opened between the conduit 6 and the conduit 9 in the pilot valve 1 so that the pressure of the starting air again prevails above the piston 26 of the slide valve I I. The spring 21 then forces the slide valve downwards so that the valve piston 29 of the slide valve shuts off the supply of compressed air to the starting air valves 23. The fuel supply to the fuel injection valve 61 is then controlled by more valve 1.

or less turning of the control wheel 2 to the left within the angle 71, Fig. 11. The cam I65 is then free to move past the tappet I54, as obvious from Fig. 6.

If it is now desired to reverse the engine, the control wheel 2 is turned to the right past the position I66 and the engine is stopped by means of the starting air or by other known means. During the return motion to the position I66 the cam I3 due to the weakness of the spring I5 passes the valve tappet 20 without actuating the same, as shown in Fig. 5. When the control wheel has returned to the stop position I66, the cams 58 and 63 have returned the bell crank lever 68 to the position illustrated in Fig. 3, in which the sleeve 4| on the starting air distributor shaft 40 has also returned to the position illustrated in Fig. 3. In this position the starting air distributors do not admit compressed air to the conduits 36, 39, which are instead connected with the atmosphere, and consequently the starting air valves 23 are kept closed. If the control wheel 2 is now turned to the right from the position I66, the roller 64 at first travels up the cam 63, the roller 59 moves towards the lower portion of the cam 58 and the bell crank member 66 is swung to the left in Fig. 3 so that the arm BI is swung downwards. The rod 62 and the arm 45 are then pulled downwards and the arm 46 movesthe sleeve 4| to the right in Fig. 3 and to the left in Fig. 1, respectively, so that the astern cams 43 are disposed just below the pertaining valve stems 48 and one of the cams 43, if a sufficient number of cylinders are provided with starting air valves, forces the pertaining valve stem 48 upwards.

The turning of the control wheel 2 to the right past the position I66 causes the cam I4-on the disk I2 to actuate the valve tappet 26 of the pilot The piston valve I1 is thereby forced upwards and the conduit 9 is connected with the atmosphere in the same way as at the above described start ahead. The chamber on top of the piston 26 is then no longer under the pressure of the starting air but under atmospheric pressure and the starting air in the chamber 24 forces the slide valve II upwards against the action of the spring 21. The slide valve piston29 opens the air passage to the conduits I84, 22 and compressed air is admitted to the starting air valves 23 and. through the conduit 52 to the starting air distributors. The engine is then at first braked by the starting air supplied to the cylinders, and after having stopped the engine starts in reverse direction in the same manner as at the start ahead, and runs in reverse direction on the starting air.

During the above mentioned turning of the control shaft I to the right past the position I66 the cam I65, Fig. 6, at first forces the tappet I55 downwards so that the sliding member I56 is moved downwards together with the arm I58, whereas the arm I60 forces the valve tappet I62 and the piston valve I5I upwards. However, as long as the cams of the fuel pumps are in position for operation ahead the tappet I55 prevents the wheel 2 from being turned so much to the right that fuel injection starts with the engine running in reverse direction, i. e. the control shaft I is prevented from turning past the position II in Fig. 11. The displacement of the piston valve I5I upwards causes interruption of the connection between the housing I 42 and the atmosphere,

and instead a connection is established from the I housing I42 through the conduit I44, the chamher I45, the grooves I53, the chamber-I4! and the conduit I48 to the conduit 0, which is under the pressure of the starting air. The starting air then acts upon the piston I 43 and forces said piston downwards together with the spindle I4I, Fig. 6, which in turn depresses the arm I39 and thereby forces the clutch member II4 to the left in Fig. 6 out of engagement with the clutch member I I3 against the action of the springs I20. As soon as the motor starts to run in the reverse direction on the starting air, the sprocket I04 turns the angle a relatively to the shaft 103 in opposite direction to the arrow in Fig. 7. The jaws I06, I01 are then contrary to the prior conditions brought into engagement with the jaws H2 and III, respectively. Simultaneously, the jaws I I1 and H8 of the sprocket I04 move across the jaws H6 and H5, respectively, so that said jaws are just clear of each other. During this mutual rotation of the sprocket I04 and the clutch member II4 the collar I24, which by the key I25 is prevented from turning relatively to the clutch member I I4, is screwed away a distance on the collar I23 and thereby displaced to the left in Fig. 6. During this displacement the bell crank lever I21, I28 is swung to the left and the rod I36 moved downwards so that the double armed lever I3I is brought to the position Astern, Fig. 6. The angle member I35 is then turned to the right so that the cam I65 is free of the tappet I55. The springs acting upon the piston valve II and the valve tappet I 62 and the air pressure acting upon the piston valve then displace the sliding member I56 and consequently the tappet I55 upwards to normal position. When the piston valve I5I is moved downwards, the connection between the conduits I44 and I48 is interrupted and a connection is instead established from the housing I42, through the conduit I44, the chamber I45, the grooves I53, the chamber I49 and the openings I50 to the atmosphere. The pressure on the piston I43 is thus relieved and the springs I are able to move the clutch member II4 into engagement with the clutch member II3 but with the jaws H5, H6 disposed on opposite sides of the jaws H1, H8 with regard to the position disclosed in Fig. 8. When the springs I20 move the clutch member II4 to the right the bell crank lever I38, I39 forces the spindle I4I and the piston I43 back to the position, in which said parts are illustrated in Fig. 6. During the movement of the clutch member II4 to the right said member is. displaced axially relatively to the collar I24, which remains in the screwed out position. The sprocket I04 is now locked on the shaft I03 in the new position, in which the cams IOI of the fuel pumps are displaced the angle a relatively to the position, which they had, when the motor was operated ahead. The rod I also remains locked in the lower position, since the collar I24 is still screwed out from the sprocket I04 and the screw threaded collar I23, and the angle member consequently remains locked in the position, in which it is swung to the right in Fig. 6 so that the cam I65 is free to move past the tappet I whereas the tappet I54 is now in the path of the cam I and prevents turning of the cam I65 to the left past the position I61.

The control wheel 2 is now free to be turned further to the right past the position I68, in which fuel injection starts in the same manner as at the operation ahead. The fuel supply is then controlled by movements of the control shaft I from the position II to the position III;

err

i. e. within the angle 72 in Fig. 11. The roller 9| makes the same movementsin the guide way 86, when the control shaft I is turned to the left and. to the right, and consequently whenthe control wheel 2 is turned to the left or to the right the pump plungers of the fuel injection pumps are actuated in the same manner. When fuel injection has started, the cam H on the disk I2 has passed the valve tappet 20 and the compressed air in the conduit 6 has forced the piston valve I! downwards. The compressed air is then again admitted to the slide valve II so that the same air pressureprevails above and beneath the slide valve piston 26. Consequently, the spring 21 moves the slide valve downwards so that the supply of compressed air to the starting air valves and the starting air distributors is interrupted.

The adjustment or control of the fuel supply to the motor during operation in reverse direction is hereafter achieved in the same manner as described hereinabove in connection with the operation of the motor ahead, the only difference being that an increase of fuel supply during operation in reverse direction is produced by an increased turning of the control wheel 2 to the right from the position I68, Fig. 2.

During the return of the control wheel to the stopposition I66 from operation astern, the cam l I4 passes the valvetappet 20:without actuating the same. During the return movement from the operation astern to the stop position I66 the starting air distributor cams are returned to the normal position illustrated in Fig. 3, whereas the angle member I35; remains in astern position as does also the reversing gear, Fig. 6, and the cams for the fuel pumps. since the collar I24 remains screwed out from the screw threaded collar I23 on the sprocket I04. thereafter turned to the left, in order to start the engine ahead, the cams 42 are moved just before the valve stems 48 and the pilot valve I brings the conduit Sin connection with the atmosphere so that the pressure of the starting air may displace the slide valve II downwards. Thus starting air is admitted to the starting air valves 23 and the starting air distributors as above described. Furthermore, the. cam I65 actuates the tappet I54 thereby causing the sliding member I56 to be displaced downwards and the clutch II 3, II4 to be released. When the motor then starts to run ahead, the sprocket I04 turns the angle a on the shaft I03;and,returns:to the.posi-. tion illustrated in'Figs. 7 and8. The collar I 24 isthen screwed-towardsthe sprocket I04sandthe angle member I35 is returned to the. position illustrated in Fig. 6. Sincethetappet I54 isnowfree of the cam I65 the piston valve I5II closes and the clutch member I I4 is brought intoen gagement with the clutchmember I I3, by the springs I20 and thereby locks-the, sprocket I04.

in the position illustrated in the drawings. The further operations atthe operationof the motor ahead arev identical with the operations above described in connection. with operation of the motor ahead.

The blocking mechanism above described and illustrated in the drawings should only be .considered as an example, and the details of the invention may naturally be modified in several nection with reversing gears forshafts for con.

When the control wheel'is For instance, the blocking mechanism.

trolling inlet and/or exhaust valves of a reversible internal combustion engine or for a shaft, which operates the valves as well as the fuel pumps of such an engine. The mechanism according to the invention has been described hereinabove in connection with a control mechanism of which the invention forms a part and in which the mechanism according to the invention serves to prevent movement of the control member into not desired positions during the rotation of the fuel pump control shaft in either direction, but the mechanism according to the invention may naturally be combined with other control mechanisms or be employed in other combinations. The sprocket I04, which drives the fuel pump control shaft I03, illustrated in the drawings, may naturally be locked by other means than the illustrated clutches. The locking of the sprocket I04 or the like must not always depend upon a blocking mechanism for preventing fuel supply in non-desired positions of the cam shaft or other controlling means. The mechanism according to the invention may naturally be employed in connection with any type of reversible internal combustion engine.

What I claim is:

1. In a reversible internal combustion engine having a control member movable in two opposite directions and adapted for reversing the direction of rotation of the internal combustion engine and/or for controlling the fuel supply of the internal combustion engine in both directions of rotation a blocking member, which may be set in two different positions and which is provided with two stops, one of which is always in g the path of the movable control member in either of said positions, said blocking member being arranged, depending upon the momentary direction of rotation of the engine, to take the position, in which the control member is prevented from being set in positions causing fuel supply for operation of the engine in the opposite direction of rotation.

2. The improvement according to claim 1, characterized by this that the blocking member comprises an angle member swingable on a pivot to two difierent positions and provided with a lever arm connected with a member, which according to the direction of rotation of the engine takes two different positions.

3. The improvement according to claim 1, characterized by this that the blocking member comprises an angle member swingable on a pivot to two different positions and provided with a lever arm connected to a member, which according to the direction of rotation of the engine takes two different positions and further characterized by the fact that the stops are displaceable in the blocking member and arranged, when displaced, to actuate a sliding member, which is connected with a valve adapted to control the pressure medium supply to a displaceable piston which according to the open or closed position taken by said valve releases a locking device for a driving member of a shaft for controlling fuel pumps and/or valves, which driving member may be set in two different turning positions relatively to said shaft, or leaves said locking device unactuated.

4. The improvement according to claim 1, in which a driving member of a shaft for controlling fuel pumps and/or valves of the engine is coupled to said shaft by means of a slipping clutch, characterized by this that the driving member is arranged to co-operate with a releasable claw clutch or the like, which is arranged upon engagement to lock the driving member relatively to the shaft in either of the positions determined by the slipping clutch, and that one member of the claw clutch is provided with screw threads, with which a collar provided with corresponding screw threads and displaceable but non-rotatable relatively to the other clutch member co-operates in such a manner that said collar according to the relative turning position of the clutch members is displaced axially in one direction or the other, and that means are provided for transmitting said movement of the collar to the adjustable blocking member.

5. The improvement according to claim 1, characterized by this that the stops are displaceable in the blocking member and arranged, when displaced, to actuate a sliding member, which is connected with a valve adapted to control the pressure medium supply to a displaceable piston which according to the open or closed position taken by said valve releases a locking device for a driving member of a shaft for controlling fuel pumps and/or valves, which driving member may be set in two different turning positions relatively to said shaft, or leaves said locking device unactuated.

- ALFRED NlisHoLM. 

